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zipcodes.pro — ZIP/21133

21133

ZIP 21133 is Randallstown, Maryland, in Baltimore County; area codes 443, 410 and 667; Eastern time.

Type
Standard
Time zone
America/New_York
County
Baltimore
Population
31,398
Coordinates
39.3784, -76.8113
☼ Live from 21133 — Randallstown, MD

Weather right now

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Local time: —

Where 21133 is

Approximate ZIP boundary (Census ZCTA 2020). ZIP codes are mail routes, not areas, so the shape shown is the Census tabulation area that approximates it.

★ Weird and wonderful facts about 21133
  • 🔢 Type 21133 into a pocket calculator and turn it upside down: EEIIZ — not quite a word, sorry.
  • ➕ As a number, 21,133 = 7 × 3019. Its digits add up to 10, a total 513 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101001010001101
  • 🏠 Its numerical neighbours: 21132 (Pylesville, MD, 30 mi away) and 21136 (Reisterstown, MD, 5 mi away).
  • 🔄 Backwards, 21133 becomes 33112 — and that is a real ZIP code: Miami, FL, 961 miles away.
  • 👥 15 other ZIP codes are made of exactly the same digits (11233, 12133, 13123, 13132, 13312, 13321, …). The farthest-flung twin is 33112 in Miami, FL, 961 miles away.
  • 🧭 Farther north than 51% of all ZIP codes, and farther east than 82%.
  • 🎯1,156 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 21133 and you would come out at 39.38°S, 103.19°E — 876 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 57m of daylight. Shortest: 9h 23m.
  • 📏 At 9.0 square miles of land, 21133 is bigger than 26% of ZIP codes — room for about 6.8 Central Parks.
🌙 The sky over 21133 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population31,398This ZIP31,398
Households12,204This ZIP12,204
Housing units12,460This ZIP12,460
Median age47.1This ZIP47.1Maryland39.4US 38.9
Median household income$80,480This ZIP$80,480Maryland$103,678US $80,734
Median home value$322,800This ZIP$322,800Maryland$419,900US $332,700
Median gross rent$1,556This ZIP$1,556Maryland$1,705US $1,413
Bachelor's degree or higher33.3%This ZIP33.3%
Mean commute31.8 minThis ZIP31.8 min
Population density3,503.9 / sq miThis ZIP3,503.9 / sq mi

Business and tax activity

Business establishments459This ZIP459
Employees6,094This ZIP6,094
Annual payroll$312,449,000This ZIP$312,449,000
Tax returns filed15,510This ZIP15,510
Total adjusted gross income$976,200,000This ZIP$976,200,000

Land area

Land area8.96 sq miThis ZIP8.96 sq mi
Water area0.01 sq miThis ZIP0.01 sq mi

Other place names in 21133

Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.

ZIP codes near 21133

ZIPCityDistance
21163 Woodstock, MD 3.4 mi
21244 Windsor Mill, MD 3.5 mi
21117 Owings Mills, MD 3.9 mi
21136 Reisterstown, MD 4.6 mi
21208 Pikesville, MD 4.7 mi
21282 Pikesville, MD 4.8 mi
21104 Marriottsville, MD 5.8 mi
21207 Gwynn Oak, MD 6.2 mi
21153 Stevenson, MD 6.5 mi
21215 Baltimore, MD 7.3 mi

Find every ZIP code within 10 miles of 21133 →

Questions about this ZIP code

Where is ZIP code 21133?

21133 is in Randallstown, Maryland, in Baltimore County, part of the Baltimore-Columbia-Towson, MD metropolitan area. Its published point location is 39.3784, -76.8113.

What county is 21133 in?

21133 lies in Baltimore County.

What area code is 21133?

Randallstown uses area codes 443, 410 and 667, from NANPA's telephone records.

What time zone is 21133 in?

21133 uses America/New_York.

How many people live in 21133?

About 31,398 people live in ZIP code 21133, in 12,204 households, at 3,503.9 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What is the median household income in 21133?

$80,480 a year, against $103,678 across Maryland.

What ZIP codes are near 21133?

The closest are 21163 (3.4 mi), 21244 (3.5 mi), 21117 (3.9 mi), 21136 (4.6 mi) and 21208 (4.7 mi).

Is 21133 a PO Box ZIP code?

21133 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “21133 ZIP Code — Randallstown, Maryland (Baltimore County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/21133

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